But Shields took a two-point lead into the second round, and her superior speed proved too much for Volnova.

WSJ: 2012 London Olympics: Shields Gives U.S. Shot at Boxing Gold

In a blistering semifinal against Marina Volnova, of Kazakhstan, Shields came out swinging from the opening bell and the two fighters traded shots in a scrappy opening round.

WSJ: 2012 London Olympics: Shields Gives U.S. Shot at Boxing Gold